Windows 10 introduces a new user agent string for phones – based on our new desktop user agent string – designed to get the most modern, interoperable content for the mobile web. Sites inspecting the user agent string for analytics should be aware of the new string, but we continue to believe that feature detection rather than browser detection is the best solution for web developers writing interoperable content.

Mobile web and apps interoperable by default

The new rendering engine will be used for all web pages loaded in the browser on Windows 10 phones. Like on PCs, “x-ua-compatible” tags will no longer be supported to force older compatibility document modes. This ensures that sites on the mobile web will always get the latest, most interoperable engine.

Starting in Windows 10, Universal Apps powered by the new rendering engine will always use the latest update to the engine installed on the device. For application compatibility, Windows Phone 8.1 and earlier apps powered by WebBrowser or WebView controls will continue to be powered by the appropriate version of Trident.

Try it out and share your feedback

You can download the Windows 10 Technical Preview for phones today via the Windows Insider program, and share feedback directly with our engineering teams using the Windows Feedback app included in the preview. We also welcome feature requests and developer feedback via the Internet Explorer Platform Suggestion Box on UserVoice, @IEDevChat on Twitter, and in the comments below. We’re eager to hear your feedback and use it to make the mobile web a better experience for customers and developers alike!